Taking off from the 18 on a designed run, David Ash ran straight toward the end zone until he couldn’t run any further. From the two-yard marker, the Texas sophomore quarterback hurdled himself forward at the same moment three Oregon State defenders converged at the goal line, bounding over the dam of Beavers and into the end zone to pull Texas within a field goal, 20-17, in the third quarter of Saturday’s Valero Alamo Bowl in San Antonio.

As Longhorns teammates patted him about the helmet in jubilation, Ash — with the ball still in hand — spiked it hard against the turf in front of him and let out a guttural scream filled with both adrenaline and emotion.

“Sometimes you just have to — for lack of a better phrase — you’ve gotta let your hair down a little bit, and I think he kind of did that the other night,” Belton head coach Rodney Southern said.

With that one play, Southern knew the old David was back. Not that he’d gone anywhere, but given Ash’s earlier first-half struggles — when he was just 7 of 13 for 53 yards — and during a few bad games earlier this season, Southern was happy to see his former pupil showing once again what he was capable of doing.

“I saw a quarterback having fun,” Southern said Wednesday. “The thing that jumped out at me is I know how good a competitor he is, and I was excited just like everybody else with the fact that he was being competitive.”

Ash said it himself in the post-game interview room: he was just having fun out there.

“I think at that point, you just start reacting. It’s not really designed that way, just kind of happens that way,” said Ash, who is now 2-0 in bowl games at Texas. “Whenever players play hard and have a little freedom to play, they’ll make plays for you.”

Two series later, Ash once again reminded his former skipper of the player that once took over a game against Harker Heights, leading the Tigers back from a two-score deficit to edge the Knights 41-37 for the team’s first victory of the 2010 season following an 0-4 start.

“Being competitive is part of his nature — he’s always been that way — and sometimes that emotion, when it does come out for a guy (from whom we) haven’t seen a lot of that, you know it’s genuine,” Southern said of Ash’s in-game fire. “The other night he was excited about playing the game.”

Using both his powerful legs and his even stronger arm, Ash spearheaded the Longhorns on back-to-back fourth-quarter scoring drives — finishing a perfect 7 for 7 passing for 113 yards and two touchdowns — in a come-from-behind 31-27 victory over No. 13 Oregon State.

“They put him into position to make plays,” Southern said. “They let him throw the ball, because he can throw the football as well as anybody in the country.”

On the first of those final drives, Ash knew he had to make a play on third-and-4 from the Beavers’ 15-yard-line and Texas trailing 27-17 in the fourth quarter. Shaking off a blitz from linebacker D.J. Alexander, Ash rolled to his left before lobbing a cross-body pass to Jonathan Gray racing down the left sideline in front of him for a touchdown.

“(Those) are the types of plays the quarterback has to make to win games,” longtime Texas head coach Mack Brown said.

Southern credited new co-offensive coordinator Major Applewhite’s experience as a quarterback at Texas and his comfortability in his first game as a play caller with Ash’s second-half emergence.

“At some point, you’ve got to say ‘Who’s your play maker?’ If it’s not your quarterback, then it’s a running back or receiver, (but) 9 out of 10 it’s the quarterback,” Southern said. “And I think they let that happen the second half and you could see everybody was more comfortable.”

Applewhite in term used a mantra that served him well during his own playing days at Texas from 1998-2001.

“If you have weapons, you use them,” Applewhite said, referring to a concerted effort to force the ball to speedy playmakers Marquise Goodwin and D.J. Monroe.

But through all the criticism he heard about Ash’s ability to be the quarterback Texas fans have craved since the days of Vince Young and Colt McCoy, Southern for one has never lost faith.

“In 26 years of doing this, he’s the best one I’ve ever been around, and I still believe that,” Southern said of Ash.

“What he’s got to do now is truly become — which he can — the leader and the mental leader of what they want to do offensively, and to get them to a point where (Texas) is back in the discussion for a national championship every year, and he’s very capable of doing that.”